Method of making mining machine chain cutter bits



F. L. FULKE I Nov. 15, 1938.

METHOD OF MAKING MINING MACHINE CHAIN CUTTER BITS 4 Original Filed May 22, 1930 2 Sheets-Sheet 1 b m w M 4 I N Y; ill": a L m 0N mm MM W .w. m. N :M 4. P a 1 .N mm m. 0 Y\ b ,\\I A I 0, w m I 0 0 A .D

m PT; v m Q ATT'Y Nov. 15, 1938. F, F KE 2,137,215

METHOD OF MAKING'MINING MACHINE CHAIN CUTTER BITS Original Filed May 22, 1930 2 Sheets-Sheet 2 as 0 'V 55 54 f/VVENTOF?! Q F/an/r L. Fu/A'e,

r 9 5 17 aflwmm Patented Nov. 15, 1938 PATENT OFFICE METHOD OF MAKING MINING MACHINE CHAIN CUTTER BITS Frank L. Fulke, Terre Haute, Ind., assignor to The Jeffrey Manufacturing Company, Columbus, Ohio, a corporation of Ohio Original application May '22, 1930, Serial No. 454,561, now Patent No. 2,036,327, dated April 7, 1936. Divided and this application October 19, 1934, Serial No. 749,104

8 Claims.

My invention relates to improvements in mining machine chains and more particularly to the bit carrying links of said chains, and to cutting bits for mining machine chains.

It is one of the objects of my invention to provide an improved form of bit carrying link, and bit therefor, which link will permit of a Wide variation in the adjustment of the bit carried thereby, so that only-one form of link need be provided.

It is a further object of my'invention to provide a bit, which while being preferably applicable for use in connection with my particular form of link may also be applicable for use with the standard commercial form of link now in use and which may be cheaply manufactured. It is another object of my invention to provide a bit having a plurality of cutting points each of which, by a simple adjustment of the bit holder may be presented in cutting position.

It is a further object of my invention to provide a cutter bit which has sharpened flaring cutting edges adjacent the points of the bit so that, in the event that the point of the bit does not remove the material to be cut, the edges will come into cutting operation.

It is a further object of my invention to provide a bit which geometrically renders itself to drop forging or stamping from sheets of material in multiple grouping without waste of material and to provide a bit with a minimum weight of material per point.

Other objects of the invention will appear hereinafter, the novel features and combinations being set forth'in the appended claims.

For the purpose of disclosing my invention 1' 'have illustrated certain embodiments thereof in the accompanying drawings in which- Fig. 1 is a side elevation of a cutter chain embodying my improved form of bit link and showing my improved form of bit supported therein;

Fig. 2 is a front elevation of the chain, the chain guide being shown in section, and showing the bits of the successive links in various adjusted positions;

Fig. 3 is a detailed sectional view showing the bit clamping means of the bit link illustrated in Fig.

Fig. 4 is a detailed sectional view showing the bit clamping positioning means;

Fig. 5 is a sectional view .of the bit link showing the oiling means;

Fig. 6 is a front elevation of the front bit clamping member of the type illustrated in Fig. 7 is a front elevation of the rear bit clamping member; 7

Fig. 8 is a side elevation of one embodiment of my bit; i r

Fig. 9 is a front elevation thereof;

Fig. 10 is a rear elevation thereof;

Figs. 11 and 12 are respectively front and sectional views of, a modified form of my bit;

Fig. 13 is still another modified form of my bit;

Fig. 14 is a front elevation of a further modified form of my bit;

Fig. 15 is a plan view of a layout on a metal sheet showing how my improved form of bit may be stamped and drop forged from sheet metal;

Fig. 16 is a side elevation partially in section of the ordinary commercial form of bit link showing means for clamping my improved bit in position;

Fig. 1'7 is a modified form means; i

Fig. 18 is a detailed section of Fig. 16; and

Fig. 19 is a detailed section on the line I9 l9 of Fig. 17. v

The present application is a division of my co-pending application Serial No. 454,561, filed May 22, 1930, now Patent Number 2,036,327, dated 'April 7, 1936, for an Improvement in mining chain cutting bits.

In the embodiment illustrated in Figs. 1 to 7, the bit carrying link I is provided with a bit carrying head 2, which is preferably cylindrical in shape and is laterally offset as illustrated in Fig. 5. This head is arranged intermediate of the ends of the'link I, being formed integrally therewith, and the two faces are identical so that theposition of the link may be reversed. Under such circumstances, however, of course, the head will be thrown on the opposite side of the line of travel. The links I are connected together by connecting links 3 which are of the usual formation and to provide for such connection each of the bit carrying links is provided with pivot pin openings 4 extending therethrough and into which the connecting pins are adapted to pass. These openings are lined with hardened bushings 5.

' For insuring the lubrication of the pivoted connections I provide each link with a centrally disposed well 6, preferably formed in the link at the time the same is drop forged, and having its front closed by a closure plate 1. Recesses 8 are formed in the side walls of the well 6 which communicate with the pivot openings 4 so that the of link and clamping on the line 18-48 lubrication contained in the well will flow to the pivot points. For preventing the bushings 5 from rotating, each bushing is provided with a slot 9 into which takes the end of a locking bar I0 arranged in the well 6 and extending through the recesses 8. Any suitable fitting as Il may be provided in a counter-sunk recess I2 in the top of the link I whereby the lubrication may be fed to the well.

The ofiset head 2 is centrally bored at l3 to receive the bolt M by which the clamping members for the bit are secured in position. The rear clamping member I5 has its top front face rearwardly and upwardly inclined as at I6, being fiat, and its outer edges surrounded by a lip II. This face is substantially triangular in shape and by the projection of the flanges I! a flat bottom triangular recess is provided. The remaining portion of the clamping member is preferably cylindrical to coincide with the cylindrical head 2.

The front clamping member I 8 coincides in shape to the rear clamping member l5 and is provided with a forwardly and upwardly inclined clamping face [9 which coincides with and lies parallel to the face l6 of the rear clamping member. The bottom edge of this clamping member is provided with a lug 20 which rests against the front faceof the clamping member IE to compensate for the thickness of the bit to be clamped between the twomembers. Each of the clamping members is provided with a central opening to receive the bolt I4 and the opening of the front clamping member is internally screw threaded to receive the screw threads 2| of the bolt I4. The rear clamping member I5 is maintained against longitudinal displacement on the bolt. M by means of a set screw 22, the end of which takes into an annular groove 23 in the bolt. This arrangement permits of the movement of the front clamping member by the rotation of the bolt relatively to the rear clamping member. Both clamping members are rotatable on the bolt id, to adjust their clamping faces,

. and with them, the bit to various positions, and

for maintaining the clamping members in their various adjusted positions, I provide a pin 24 which takes into apertures 25 and 26 in the front and rear clamping members and into recesses 21 in the face of the head 2. It will be noted that I provide a plurality of these recesses 21 whereby the bit may be adjusted on the head 2 to obtain the most beneficial cutting position for that particular link, and it will be noted from Fig. 2' that by adjusting the successive bits in the chain a proper kerf may be obtained. It will also be noted that by merely reversing the link, thereby throwing the head 2 to the opposite side of the line of travel, the width of the kerf may be adjusted as desired.

The bit which I provide, used in connection with the above described link has a plurality of cutting points and in the structure illustrated, having particular reference to Figs. 8, 9 and 10 is provided with three cutting points 28 connected by sharp cutting edges 29 which outline an equilateral triangle. The face or cutting side of the bit is concaved and the back of the bit is convexed so that the bitforms a triangular concave-convex figure, the front faces 30 and the rear faces 3| of which form three isosceles triangles.

In clamping the bit in position it will be note that the clamping face l9 engages in the front face of the bit and lies flat and against one of the triangles 30 while the clamping face 16 re calves and backs up the rear face of the triangle.

If desired the bit may be of the structure shown in Figs. 11 and 12 wherein the front face is perfectly flat and is! provided with a central opening 32 to receive a securing pin. The rear face has the same configuration as the rear face of the structure shown in Figs. 8 and 9 and is and 9 may be formed by drop forging, stamping,

rolling or otherwise. And it will be noted from the layoutof the stampings on the sheet that the bits may be formed with aminimum of waste of material.

Drop forging, stamping, rolling, and hand operations for shaping metal, are of course well known, but my invention is not broadly directed to drop forging, stamping, rolling, or hand oper-- ations, but is the adaptation of these well known methods of shaping sheet metal, to the particular and specific purpose of forming mining machine cutter bits. That is to say, those acquainted with such well known methods of shaping sheet metal will be able to understand how to carry out my improved methods to efficiently produce mining machine cutter bits from strips of sheet metal.

My improved method contemplates the making of mining machine cutter bits having a plurality of cutting points which comprises the formation in a sheet of metal of a plurality of recesses having a plurality of triangular opposing faces, and dividing the sheet metal at the edges of the recesses to form a plurality of cutter bit points radially disposed relative to the center of each blank. My improved method of making such mining machine cutter bits comprises the formation from a sheet of metal of cutter bit blanks by recessing adjacent equilateral triangles of the sheet metal, and dividing the sheet metal at the edges of the equilateral triangles to form cutter bits with radially disposed cutting points connected by cutting edges. In forming such cutter bits from sheet metal, a strip of material may be provided having a width equal to twice the width of a single bit measured from one point perpendicularly to the opposite side, and forming in such strip of metal triangular recesses with their edges merging so as to use nearly all the metal in the strip, and finally severing the re cessed portions along such edges in equilateral triangular formation.

An integral piece of material may be provided of predetermined size and area, recesses in such material drop forge-d in multiple group formation, without waste of material, separating the blanks from the group and providing each blank with a plurality of cutting points. That is to say, cutter bits are formed by drop forging recesses in a sheet of metal to predetermine a plurality of closely adjacent blanks, and stamping the blanks from the sheet for forming bits each having a plurality of cutting points. By thus drop forging and stamping from a sheet of material, recessed cutter bits may be produced,

each having-a plurality; of cutting points connected by equilateral edges. The cutter bits may be triangular in shape, each having a plurality in multiple group formation as. illustrated in Fig 15, this being in accordance with thepredetermined size of thecutter bit. The recessed areas areseparated along the lines indicated in Fig.

15, to form a plurality of. recessed cutter bits each having a plurality of cutting points whereby nearly. all of thematerial in said strip is used in said cutter bits.

As above stated, drop forging, stamping, rolling, and hand operations, for the shaping of sheet metal, are old and well known. These involve machines and tools which I do not claim to have improved. My improvement contemplates the use of old tools heretofore used for the shaping of metal, but adapting the use of such tools to a new method because the steps employed give such a shape to the metal as to produce a new article of manufacture, namely, a mining machine cutter bit.

For instance, I may, by means of manually operated punches and dies, form the recesses in the strip of metal of Fig. 15, one after another, and then shear the blanks apart to form the cutter bits. Or I may drop forge the recesses, one after another, and cut the recessed blanks apart to form the cutter bits. 01' I may stamp out from the strip a triangular cutter bit by recessing and cutting by means of well known machinery modified to produce the desired shape to secure the three-pointed recessed sheet metal bit.

While I resort to well known machinery and old methods of shaping metal, these are modified and associated in new combinations to produce a new and useful result in that a triangular three-pointed cutter bit is very efficiently produced from a sheet of metal. In. other words, my steps are carried out to a further extent than a mere shaping of a piece of metal into a blank having no utility. My improvements include the further association of the various steps and their continuance until the blank is in shape to act as a cutter bit for mining machines. v

In Fig. 16 I have illustrated a form of clamping member which may be used on the present commercial type of bit link. This bit link as illustrated is provided with a longitudinally ex tending opening 35 generally rectangular in crosssection as is the character of bit now in commercial use. The bit is secured in position by means of a set screw 36. My present type of clamping means comprises a. rear clamping member having a shank 31 provided with a head 38 overhanging and resting upon the top of the link as at 39. This head has a rearwardly and upwardly inclined triangular face 49 surrounded by a rim 4!. Cooperating with the rear clamping member is a front clamping member having a shank 42 provided with a lug 43 taking into a recess 44 on the front face of the shank 31 and provided with a head 45 overhanging and. resting upon, as at 46, the top of the link. This head has a front face 47 slightly forwardly extending to cooperate with the face 40 for clamping the bit between the same.

The lower ends of the two shanks at their adjacent faces are inclined away from one another as at 48 so that, when the clamp as a whole is lifted slightly out of its'socket 35, the two clamping members may be separated, and to pre vent their complete withdrawal I provide a shoulder 49 on the lower end of the front shank which will be. engaged .by the edge. of the set screw unless the same is withdrawn to a greater extent,

. and prevent the complete removal of the clamping member. In order to force the clamping member upwardly fo-r the purpose of renewing or changing the bit I provide a spring 50 in the bottom of the socket 35.

In .the structure .illustrated'in Fig. 1'7 I show a modified form of link which may be reversed.

Inthis form: oflink the socket is-rounded and the head is screw threaded as at and 5| to receive, from either end, the holding screw 52. The shanks of the front and rear clamp-ing members 53 and 54 are rounded and the shank of the front clamping member 53 is' provided with a conical recess 55 for reception of the conical end of the set screw 52, whereby when the screw is turned up it will not only force the' two clamping members together but will tend to draw the member 53 down onto the member 54.

Obviously those skilled in the art may make various changes in the details and arrangement of parts without departing from the spirit and scope of the invention as defined by the claims hereto appended, and I therefore wish not to be restricted to the precise construction herein disclosed.

Having thus described and shown an embodiment of my invention, what I desire to secure by Letters Patent of the United States is:

1. The method of making mining machine cutter bits having a plurality of cutting points which comprises the formation in a sheet of metal of a plurality of recesses having a plurality of triangular opposing faces, and dividing the sheet metal at the edges of the recesses to form a plurality of cutter bit blanks of equal size and shape to afford a plurality of cutting bit points equal in number to said plurality of opposing faces and radially disposed relative to the center of each blank.

2. The method of making mining machine cutter bits which comprises formation from a sheet of metal of cutter bit blanks by recessing adjacent equilateral triangles of the sheet metal, and dividing the sheet metal at the edges of the equi-lateral triangles to form cutter bits having radially disposed cutting points connected by cutting edges.

3. The method of forming cutter bits from sheet metal which consists in providing a strip of metal having a width equal to twice the width of a single bit measured from one point perpendicularly tothe opposite side, forming triangular recesses with their edges merging so as to use all of the metal in the strip and severing the recessed portions along such edges in equilateral triangular formation.

4. The method of forming cutter bits from an integral piece of material which consists in providing such material of predetermined size and area, drop forging fiat faced recesses in such material in multiple group formation without waste of material, and separating the individual blanks from the group to provide each blank with a plurality of cutting points equal in number to the fiat faces of the recess therein.

5. The method of forming cutter bits which consists in drop forging and stamping from a sheet of metal triangular cutter bits each of the fiat sheet of metal which consists in shaping andrecessing the metal to form three cutting points equilaterally spaced and connected by equilateral seating faces in intersecting planes to adapt the cutting bit for clamping to a mining machine chain cutter with any one of the cutting points in cutting position.

8. The method of forming a plurality of cutter bits from a flat sheet of metal with minimum waste of material, which consists in forming recesses in each of a series of closely adjacent triangular areas to form triangular fiat faces in intersecting planes, cutting the metal apart along lines bounding such areas to afford cutter bits each having three cutting points from each'of which diverge two flat inner faces and two flat outer faces adapted to be clamped to a bit holding link of a chain cutter with any one of the cutting points in cutting position.

FRANK L. FULKE. 

